Structural assembly



April 1938. E, J. w. RAGSDALE- Re. 20,689

' STRUCTURAL ASSEMBLY Original FiledJune 25, 1931 3 Sheets-Sheet l FIG. 1

i I a INVENTOR.

' EARLIWPM 7 I ATTORNEY.

.April 5, 1938. E.. J. W. ,RAGSDALE 20,639

I STRUCTURAL ASSEMBLY Original Filed June 25, 1931 5 Sheetsl-Sheet 2 INVENTOR. EARL lWRAssoALE.

Q6 4 BY ATTORNEY.

E. J. w. RAGSDALE" April 5, 1938.

STRUCTURAL ASSEMBLY Original Filed June 25, 1931 3 Sheets-Sheet 3 EAQLlWIRAcIsDALB V WKM ATTORNEY.- v

\ H o v u u v a .a////////// Reissued A r. 5, 1938 smno'rum ASSEMBLY Earl J. W. Bagsdale, Norrlstown, Pa, assignor to aeturing Edward G.- Budd Mann! 00.,1'hiladelphia, Pa., a corporation of Pennsylvania Original No. 1,966,933, dated July 11, 1934, Serial No. 546,722, June 25, 1931. Application for reissue May 18, 1938, Serial No. 80,470-

18 Claims. ((1111-79) The invention relates to sheet metal body constructions and to a method of manufacture of such bodies, as boats, pontoons, aeroplane fuselages and the like.

Experience with the building of such bodies as heretofore constructed indicates that the proper alignment of the transverse frame members and the positioning of the longitudinal members called stringers, consume more fabrication of thesemembers. 'Even under the time than the most favorable conditions, the skin or sheathing will -not absolutely conform to the contacting members of the skeleton-frame.

A troublesome andunsightly job results.

It is a main object of the invention to overcome these difficulties by providing a construction and method of manufacture in which the body to be constructed is arbitrarily divided along lines extending longitudinally thereof into transversely separated longitudinally extending sections or sub-assembliesfthesmsections being separately fabricated complete with sheathing and associated framework, after which the sections are joined together along the longitudinal- .25 1 1y extending lines f arbitrary di The invention further comprehends the strucitural features whereby-tins method of manufacture is facilitated and whereby a strong, light- -metal body results. .Such structural features include the edge conformation of the sheathing of the adjacent-sections and the manner in which the transverse frame and longitudinal members are formed to permit their easy and rapid'ioinder, as by spot welding.

This method and construction is particularly applicable to metal streamline bodies'in which the skin and framework are made of light gauge sheet metal stock, such as stainless steel, which has the desirable features of great strength, non- 40 'corrodibility, and ease of ioinder by spot weldother and runner objects and View will become apparent from the following detailed description, when read in connection with drawings formingapartofthisspecification.

- In the drawings. the invention is shown applied to 8 flying boat particuiarly'adapted for me in gliderconstruction. It will be obvious that it is equally applicable with minor variations to lnthedrawingfl. l'imiis'atopplanviewofaboatmanufaetured in aoeonhnce with theinvention, with top Fig. 2 is a sectional side elevation thereof taken on the line 2-2 of Fig. 1;

Fig. 3 is a side elevation and Fig. 4 is a bottom plan thereof;

Fig. 5 is a detail transverse sectional view taken 5 substantially along the line 5-5 of Fig. 1;

Fig. 6 is a fragmentary perspective view showing one form of diagonal joint member or gusset joining the vertical and horizontal frame members of adiacent longitudinal sections of the boat;

Figs. 7 and 8 are exploded sectional views showing the method of sub-assembly of the sections prior to. their final assembly into the complete body;

Fig. 9 is a perspective view of a structural unit employed in the construction;

Fig. 10 is a fragmentary perspective view of the longitudinal and transverse joint connecting the longitudinal sections of a modified body construction; l

Fig. 11 is a transverse sectional view through the joint of Fig. 10;

Fig. 12 is a perspective view of a diagonal structural element joining adjacent ends of the transverse frames; and 5 Figs. 13, 14 and 15 are views corresponding to Figs. 10, 11 and 12, but showing a still further modification.

The drawings (Figs. 1 to 9) show a boat assembly and this boat is shown as being con- 'structed entirely of light sheet material as stainless steel, and comprising a frame of the proper shape,- which frame has thereto a covering skin, or sheathing ll. A number of outside stringers or keclsons i! of inwardly presenting V sttionedonthe members ii-and ilwitliedges orl the plates abutting the flanges ll of the tr verse and vertical members and with the areas adjacent these edges at the ends of theplates welded to the structural member on opposite sides thereof. 1

In Figs. 7 and 8,- the method of assembling the boat structure is disclosed. The outside stringers I! on the bottom of the boat are sub-assembled on the bottom covering or sheathing, as are the inside transverse frame members it, by spot welding the flanges of the stringers to the covering. The sections 21 of the gusset are positioned and properly oriented on the transverse member i5 and welded thereto as shown. Similarly, the side portions of the boat including the covering or sheathing Ill, outside stringers l2, vertical frame members it, and the sections 26 of the gusset, are positioned in such a manner that the gusset sections 26 and 21 are properly overlapped when the sides of the boat are finally assembled on the bottom. The covering l0 on each side of the boat is provided with lateral flanges 30 and Si adjacent its lower and upper edges respectively. The flanges 30 are adapted to seat squarely on the covering ll) of the bottom section of the boat. when the sides are assembled on the bottom, these flanges 30, are welded to the covering Ill of the bottom and the overlapping portions of the gusset sections 26- and 21 are also welded together.

In order to strengthen the gusset sections a reinforcing member of channel shape cross section is inserted between the parallel plates of the gusset section. This reinforcing member is provided with side flanges 52 each having an inwardly extending ofl'set portion 54 to accommodate the offset overlapped portions 20 of thegussets. The sides 52 of this reinforcing member 50 are suitably welded, as shown, to the plates, and thus a very rigid structure is attained.

The upper section of the boat is also independently assembled. The covering I II is assembled on the transverse frame members i6. This covering extends inwardly of the frame member ii a substantial distance and is provided with inner upturned flanges 33. The outside stringers i2 are also included in this sub-assembly. The sections 21 of the gusset are positioned on the transverse frame member It so that they will engage the upper gusset sections 26 on the side members when the assembly is completed. The upper section of the boat is then assembled upon the side sections, and the flanges 3i are spot welded to the.

edges of the sheathing material III on the upper boat section. The upper sheathing Ill not being continuous but being provided with a central opening Ill permits access to the interior of the boat structure for welding the overlapped portions 2| of'the uppergussets. A closing section is designated at 42. This closing section consists of a sheet of material having upturned flanges 43 adapted to be welded to the flanges II to complete the closure of the boat structure. If desired, the outside stringer I! may be-secured longitudinally of the closing section 42 for the p se of reinforcing the same prior to the assembly of the closing section in the boatstructure, as indicated in Fig. 7.

The boat is generally shaped in the form of a streamline body, to which this structure is particularly adapted, and has a pointed bow ill, a widened portion 82 and a tapering stem 64. The transverse frames which cooperate to make up the boat structure are designed according to the respective positions which theyoccupy in the boat that in the final assembly the edge conformations and comprises a plurality of diagonals having one arm to the flanges of the channel l4 and i6 longitudinal location of the transverse members 2 overlaps .and is welded in the final assembly in structure. Thus the size of the frames located i the widened portion, as for example, where th section 5-4 if takenin Fig. 1, would be comparatively larger than the frames in the relatively small stern section, although the construction of these frames is substantially the same. In the sub-assembly of the separate longitudinal sections the sheathing or covering'is held in a suitable jig to the desired curvature. Then the outside stringers l2 and the interior frame members II and I6, suitably contoured, are secured to the sheathing. This fixes the curvature of the sheathing of the sections to the exact shape, so

through which the sections are joined will match.

Suitable trussing may be provided if desired for reinforcing the entire boat construction, and as shown in Fig. 5, this trussing is designated at 10 their lower ends secured between the two flat gusset plates 12 welded to the opposite sides of the transverse member i6. These diagonals extend upwardly toward the upper corners of the boat structure and are suitably welded to the parallel plates of the corner gussets. Where these struts or diagonals are employed the reinforcing members 50 are omitted in order to permit insertion of the diagonal members 10 between the plates of the gusset members. The members 10 are positioned between the gusset plates and perform the function of the reinforcing members 50. Longitudinally extending diagonal struts H, Fig. 2, and transverse diagonal struts as l2, 13, Fig. 1,. further stiffen the structure in regions where this is desired for taking up the stresses to which the particular structure in which the invention is embodied is subjected in use.

In the modified construction shown in Figs. 10 to 12, the adjacent longitudinally extending sections which are sub-assembled prior to the final assembly comprise the smooth outer sheathing or paneling-sections ill, the longitudinal stringers l2 having their bases'disposed against the inner face of the skin, the transverse frame members I4 and ii of flanged channel section facing outwardly and secured to the longitudinal stringers I! through angle brackets 14 spot welded through and through the other arm to the side walls of the channel stringers. This bracket connection permits flexibility of the connection between the stringers and transverse frame members allowing for tilting of the frame members with respect, to the skin to various angles dependent upon in the streamline structure.

The corners or regions of joinder of two adja- A cent longitudinal sections are in this modification reinforced by closed section chine stringers of v quadrangular cross section, the outboard angle of which is comprised of portions of the skin or sheathing l0 secured together by crimping one at 15 over an edge flange 16 of the other, and spot welding the parts together in the .crimped joint. The diagonally opposite inboard angle is 6 comprisedof separate longitudinal framing strips 11 and 18, one of which as '11, may be of angle section having one arm welded to the one sheathing section III and the other,'as 18, may be .of Z-section having one arm of the Z welded to the, 7 other sheathing section. The other arm of the the inner edge of the inwardly extending armof strip 11. The ends of the transverse frame members I4 and It abut respectively the strips 11 7 and II and are secured thereto by angle brackets 19 spot welded respectively to the side wall chan-' nels of said frame members and to the inwardly extending arms of the strips 11 and I8. All the joints so far described except the crimped joint 15, I8 and the joint between the strips 11, It can be readily made in the sub-assembly of each of the longitudinal sections out of which the complete body is built up. Ready accessibility is had by reason of the general openness of the construction, for joining the parts by spot welding.

In the final assembly of the sections the joints between I! and I8 and the strips 11 and I! are readily made, by reason of the openness of the construction, to form the closed box section-chine stringers. It will be apparent from the foregoing description and the drawings that these joints comprise overlapping portions constituting flanges projecting away from or outside of the box section itself, and are thus readily accessible for welding. It will also be noted from the above description that the stringer members I! and I Cal constituting part of the bottom section, at its margins, form an upwardly and outwardly presenting angle, or partial oropen hollow section, while the complemental members I1 and i0,

constituting part of the side section, form an inwardly and downwardly presenting angle, or partial or open hollow section. In fact, the free edge of the member" and the edge flange 1B of the sheathing may be aptly defined as joint parts carried by the sidesub-assembly, which parts, in final assembly, are arranged to overlap and be secured to the complemental parts of the margin of the bottom sub-assembly. It will be further noted from the foregoingdescription and the drawings that in this modification the line of arbitrary division, referred to in the preamble, p'iisses through the hollow corner stringer itself, some members of this stringer forming part of one sub-assembly, and other complemental members forming part of the adjacent sub-assembly. The frame members I4 and I8 are interbraced by diagonal intercom necting members in the form of inwardly facing flanged channels 80 received telescopically within theopened up ends of the outwardly facing channels of the transverse frames I4 and I6 and spot welded to the side walls of the channels. These channels may be further strengthened 'by closing them with a closing strip ll secured to the flanges of the channels.

' According to the further modification shownin Figs. 13 to 15, still greater strength is secured, such asmay be desirable in flying boat constructions. In this modification, a side and bottom section of a flying boat construction are shown, in' which the skin iii" of the bottom section is longitudinally fluted,- and outwardly facing flanged channel longitudinal stringers II" are secured through their flanges to the skin.

The bottom transverse frame members It" are of inwardly presenting flanged channel section having their bases secured to the bottom of the longitudinal stringers either through inter- .mediate gussets Bl as shown or directly without the intermediary ofgussets. The bases of the transverse members are also secured at the bottoms of the flutes of the skin, directly to the skin. The fluted skin of the bottom and the connected frame members thus form -a very strong and rigid bottom construction, well able to withstand the stresses of landing upon the water.

In this modification, the hollow quadrangular chine members connecting the side and bottom cured by spot welding to l 3 sections are formed jointly by the intersecting portions of the sheathing II" and II' and intersecting arms of angle section stringer mem-' bers 11' and It. The arms of angle members 11' are flanged and secured through the fianges to the edges of the arms of member .18 while the side sheathing 1' reinforced by the vertical transverse frames ll" similar to the bottom transverse frames l8 and secured to the sheathing in similar fashion, has its lower edge overlapping and secured to the vertical arm of the stringer member 11. The bottom sheathing is similarly secured to the horizontal arm of stringer member 18' and has its extended edge crimped, at 82, over the overlapping and Joined together outeredges of the members l1 and IB.'

hollow longitudinal chine stringer and have their wings 84' and 85 overlap the side walls of the channel section transverse frame members It" and it" and secured thereto. These gussets are flanged, at in the direction of the flanges of the frame members and form with the flanges of the frame members substantially continuous flanges transversely of the: boat a continuous reinforcing body, to which strip as 81, may be seform a closed box section'transverse frame structure, providing increased strength and finish to the interior framing.

The several modifications shown indicate that the structure and method of the invention lends itself to considerable modification in the detail of the manner of reinforcing the sheathing and in other respects to adapt the advantages of the invention to various uses and it will be obvious that in its broad aspects the invention is not limited to the particular detailed structures shown, although these are all highly practical constructions and all well adapted for joindery This invention is not limited in its application to boat structures, but employed in any hollow sheet metal body structure, such as fuselages, pontoons; etc., including land vehiclesand in the latter case, the longitudinal corner stringers are commonly known as side sills. g

In its-broader aspects as claimed in certain of I the attached claims, as well as in its narrow aspects, covered by other of the claims, it will v be understood that modification andvarlations asv clearly fall within the spirit-and scope of the invention are intended to fall within, the language and scope of the appended claims.

What I claim is:

l. A body construction having longitudinal sections thereof arranged at an angle comprising a hollow section, and a hollow longitudinal stringer along the angle between two adjoining sections, and hollow section transverse frame members secured to the walls of said longitudinal member, and'a diagonal brace of hollow cross section having parts telescoping certain wallsw of the hollow section transverse frame members and secured thereto. I

can the advantageously 2. A body construction having longitudinal sections includin'g sheathing and framing arranged at an angle to each other, said framing comprising a closed section longitudinal stringer in the angle between said sections, inwardly facing. flanged channel section transverse frame mem-v ing the flanged side walls of the channel, and

' a continuous strip closing member secured to joinedto the sheathing of the a longitudinal member of one the flanges of said frame members and the gussets and closing the channel section.

3. In a structure characterized by a plurality of unit wall sub-assemblies embodying sheathing and framing disposed at an angle to each other and joined directly to. each other at their adjacent margins, a corner fastening for securing said unit sub-assemblies in position comprising a straight sectional gusset formed in two pieces, extending diagonally across the comer and spaced from said joint, one section of the gusset being welded to one sub-assembly and the other section of the gusset being welded to another sub-assembly, said gusset sections overlapping and being welded to each other at their overlapped portions.

4. A corner fastening for securing the sectionsof a structural'assembiy together comprising a pair of plates each welded to surfaces of one section of the assembly, 'a second pair of surfaces of another section of the assembly, each plate of one pair overlapping a plate oi the and being welded thereto, and a reinforcing member extending between the plates of each pair and being welded thereto. e

5. A sub-assembly unit for a sheathed streamline body having a supporting framing, adapted to be joined to a mating, section in its margins and having its margins extending longitudinally of the longitudinal axis of the streamline body. which unit comprises sheathing and attached transverse framing together with sections of corner gussets attached to the side faces of framing, said sections being of a length adapted to overlap and be secured to complementary sections of corner gussets as attached to a similar such section.

6. A streamline body construction built up of longitudinal sections contoured to the form of the completed body, each of said sections comprising longitudinal members, transverse members and sheathing, adjacent sections secured together, the sheathing of one of said sections adjacent section, section Joined to an adjacent longitudinal member'of said adjacent section independent of the joint of said sheathing and a transverse member 01' one section joined to a transverse member of said adjacent section independent of the joints of said longitudinal members and said sheathing.

'7. A sheet metal vehicle body having generally horizontally disposed and generally vertically disposed wall sub-assembly units divided along longitudinal lines, said wall units comprehending main transverse framing and, as respects the vertically disposed wall unit at least comprehending also outer contouring sheathing, secured to said-transverse framing, said units being joined together in their margins to form between them a longitudinal joint structure of box cross'section, the horizontal wall, unithaving vertically spaced final assembly joint parts directly .enterother pair the box-section structure.

casseing into the box-section structure, the outer contouring sheathing of the vertical wall unit constituting the outer vertical wall of the box-- section structure and being joined to the vertically spaced final assembly joint parts of the horizontal wall unit along longitudinal lines disposed in regions. permitting the bringing together of the units in final assembly by relative movement edgewise of the horizontal wall unit.

8. A sheet metal vehicle body having generally .horizontally and generally vertically disposed of its longitudinal extent and constituting the outer vertical wall of the box-section structure and being joined to the spaced final assembly joint parts of the horizontal wall unit along longitudinal lines disposed in regions permitting approach movement of the units in final assembly in a direction edgewise' of the horizontal unit.

9. A sheet metal vehicle bochr having hori zontally disposed and vertically disposed sub-assembly wall units divided along longitudinal lines and embodying .an inter-unit longitudinally extending final assembly joint structure of box cross section at their meeting margins, tile horizontal wall unit comprehending marginal longitudinal framing and transverse framing interconnecting the marginal longitudinal framing, the vertical unit comprehending main transverse framing and outer contouring sheathing, the horizontal unit having a hollow outwardly open marginal portion having vertically spaced final assembly joint parts entering into the box-section structure, the-outer contouring sheathing of the vertical wall unit constituting the outer vertical wall of the box-section structure and being joined to the spaced final assembly joint parts of the horizontal wall unit along longitudinal lines spaced vertically apart.

10. A sheet metal vehicle body according to claim.8 in which the vertical wall unit has its margin entering into the final assembly joint structure iormed of hollow inwardly open 'cross section and having vertically spaced final assembly joint parts adapted, in the final assembly, to mate with and be joined to the vertically spaced final assembly joint parts of the horizontal wall unit thereby completing the box section structure.

11. A sheet metal vehicle body according to margins entering into the final assembly joint structure formed of hollow inwardly'open cross section having vertically spaced final assembly joint parts adapted in the final assembly, to mate with or be joined to the final assembly joint parts of the horizontal wall unit thereby completing 12. A sheet metal vehicle according to claim 8 in which the vertical wall unit has its transverse framing disposed inwardly of the smooth face of the outer sheathing and secured assembly joint parts parts arranged semblies.

eases side margins having spaced final assembly joint parts disposed at the opposite sides of said open .hollow section, transverse framing interconnecting said hollow section side margins, and a side wall sub-assembly including outer contouring sheathing and transverse framing, said side wall sub-assembly being iormed in its lower margin with spaced ilnal assembly joint parts including said sheathing arranged to overlap exteriorly of the body the complemental spaced final assembly joint parts of the adjacent open hollow section side margin of the bottom sub-assembly and be secured directly thereto to form therewith a completely closed box-section reinforcing structure along the longitudinal corner joint between the wallsub-assemblies.

14. A sheet metal body having a side wall subassembly unit including contouring sheathing and framing and provided with a longitudinally extending open generally inwardly presenting hollow section bottom margin having spaced final disposed along the sides of and a bottom wall sub-asbottom sheet and transverse said sheet, said bottom wall said hollow section, sembly including a framing reinforcing sub assembly being formed in the side margin thereof including the bottom sheet with spaced longitudinally extending final assembly joint in final assembly to' overlap the spaced final assembly joint parts of the adjacent open hollow section bottom margin oLthe side sub-assembly and be secured directly thereto through the overlaps to form therewith a completely closed box-section reinforcing structure along the comer joint between said wall sub-as- 15'. A sheet metal havinga bottom wall sub-assembly including longitudinally extending partial hollow section side margins, transverse framing interconnec ing said partial hollow section side margins, said partial hollow section marginal portions being of generally outwardly facing form having two spaced edge flanges. directed away fromthe interior or the section, and the side wall sub-assembly including outer and transverse ,i'raming and iormed in its lower marginwith two spaced final partial hollow 'ing of adjacent joined together sub-assemblies,

including said sheathing, arranged to overlap in final assembly both the edge flanges of the adjacent partial hollow section marginal portion of the bottom wall sub-assembly and secured thereto in said overlap to provide a closed box-section reinforcing structure along the joint between the wall sub-assemblies.

16. A sheet metal body construction built up of laterally adjoining longitudinal wall sections contoured to the form of the completed body, said wall sections each comprising sheathing and iongitudinal reinforcing members, the latter'each secured at one edge thereof, respectively, along the adjacent longitudinal margins of the sheathing of the respective wall sections, andhaving the other edge projecting tree of the sheathing, the freely projecting edges of said members being directly united and the margins of the sheathwall sections being also directly to thus form a hollow box-section the joint between the wall sections. 1'1. A sheet metal body made up 0! a bottom wall sub-assembly includinglongitudinal members forming at each side-margin an open hollow cross section upwardly and outwardly presenting structure, transverse framing interconnecting said hollow section structures, and a side wall subassembly joint parts,

stringer at assembly includingsheathing and framing and generally angular section, transverse framing interconnectlng said angularsection structures, and a side wall sub-assembly including sheathing and longitudinal framing members .Iorming at its lower margin a downwardly and inwardly presenting structure of generally angular section being united in anal assembly tojorm a box-section stringer in the region of the joint between the the points 0! union of saidxstructures lying substantially at the opposite corners of said box-section. v EARL d. W.-RAGSDAI.E.

a box-section stringer in the 

